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<h1><span class="kind-method">generate</span> method 
</h1></div>

    <section class="multi-line-signature">
      

<span class="returntype"><a href="https://api.dart.dev/stable/3.1.3/dart-core/String-class.html">String</a></span>
<span class="name ">generate</span>(<wbr><ol class="parameter-list"><li><span class="parameter" id="generate-param-options">{<span class="type-annotation"><a href="../../data/V8Options-class.html">V8Options</a>?</span> <span class="parameter-name">options</span>}</span></li>
</ol>)

      

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<section class="desc markdown">
  <p>V8() Generates a time-based version 8 UUID</p>
<p>By default it will generate a string based off current time in Unix Epoch,
and will return a string.</p>
<p>The first argument is an options map that takes various configuration
options detailed in the readme.</p>
<p><a href="https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format#section-4.3">https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format#section-4.3</a></p>
<p>0                   10                  20                  30
0 1 2 3 4 5 6 7 8 9 A B C D E F 0 1 2 3 4 5 6 7 8 9 A B C D E F
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        year-month-day                         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|          hour:minute          |  ver  | rand  |    seconds    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|var| milliseconds  |                   rand                    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                             rand                              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+</p>
<p>48 bits - year-month-day
4 bits - version
4 bits - random
8 bits - seconds
2 bits - variant
16 bits - milliseconds
46 bits - random</p>
</section>


    
<section class="summary source-code" id="source">
  <h2><span>Implementation</span></h2>
  <pre class="language-dart"><code class="language-dart">String generate({V8Options? options}) {
  var buf = Uint8List(16);

  DateTime time = options?.time ?? DateTime.now().toUtc();

  buf.setRange(
      0, 2, UuidParsing.parseHexToBytes(sprintf(&#39;0x%04i&#39;, [time.year])));
  buf.setRange(
      2, 3, UuidParsing.parseHexToBytes(sprintf(&#39;0x%02i&#39;, [time.month])));
  buf.setRange(
      3, 4, UuidParsing.parseHexToBytes(sprintf(&#39;0x%02i&#39;, [time.day])));
  buf.setRange(
      4, 5, UuidParsing.parseHexToBytes(sprintf(&#39;0x%02i&#39;, [time.hour])));
  buf.setRange(
      5, 6, UuidParsing.parseHexToBytes(sprintf(&#39;0x%02i&#39;, [time.minute])));

  var randomBytes = options?.randomBytes ?? _randomData();

  buf.setRange(6, 16, randomBytes);
  buf.setRange(6, 7, [buf.getRange(6, 7).last &amp; 0x0f | 0x80]);
  buf.setRange(8, 9, [buf.getRange(8, 9).last &amp; 0x3f | 0x80]);

  buf.setRange(
      7, 8, UuidParsing.parseHexToBytes(sprintf(&#39;0x%02i&#39;, [time.second])));
  var milliBytes =
      UuidParsing.parseHexToBytes(sprintf(&#39;0x%04i&#39;, [time.millisecond]));
  milliBytes[0] = milliBytes[0] &amp; 0x0f | buf.getRange(8, 9).last &amp; 0xf0;
  buf.setRange(8, 10, milliBytes);

  return UuidParsing.unparse(buf);
}</code></pre>
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